The Propagation of Pomegranates
By Ashley Braun
In my paper I’m going to explain to you what a pomegranate is and its care. I will also go in depth on the different methods of propagating pomegranates. Pomegranates are not widely grown in the United States mostly because of unfavorable climate, but also because the demand for pomegranates is not very high in the United States. This lack of interest created a small problem with finding strong research information about the pomegranates propagation. There are several different propagation methods used to grow pomegranates. Much work needs to be done to increase production and information about the pomegranate, but the field and interest in the rare fruit is growing and has the potential to double within the next ten years.
The pomegranate is native to the Middle East and South Asia. It has wandered over the centuries to China, India, the Mediterranean, California, and Florida. The pomegranate is one of the first five cultivated foods in the world. There are some trees in Europe that are known to be over 200 years old. Throughout the centuries it has been used widely in literature and art and was often seen as a sign of fertility or wealth. The pomegranate is very high in potassium, vitamin C, and antioxidants.
The pomegranate plant comes in either a tree or a shrub. It is usually grown for its large fruit, but there are some dwarf cultivars used primarily for landscaping or bonsai trees. The foliage is long, thin, and glossy in appearance. It produces small flowers usually one inch in diameter. The flowers come in a wide variety of colors, but the most common are orange and red. The fruit produced is usually two to five inches in diameter with a hard rind. The rind comes in many different colors from green, yellow, orange, and red. Inside the fruit are locules separated by a thin, bitter membrane. Within the locules are many small jewel-like objects called arils. The arils contain tart to sweet flavored juice and a small seed. The juice ranges in color from clear to a deep staining red.
The pomegranate is capable of growing in a wide range of soils as long as it has good drainage. It likes to be placed in an area with a lot of sunlight. You should plant the tree or shrub in early spring with rows 15 to 18 feet apart, but make sure to protect it from any late frosts that come along. Every spring you may also add a couple inches of mulch around the base of the tree or shrub. The pomegranate is tolerant of drought, but only cold hardy till 12 degrees Fahrenheit. It prefers very warm temperatures, which improve the flavor of the fruit. For mass fruit production sprinkler irrigation is preferred, but should not be utilized close to harvest time because it causes fruit cracking. The pomegranate is self-pollinating, or it can be cross-pollinated by insects. Cross-pollination also increases fruit set and quality. The plant requires very little fertilizer, around 5-8 ounces of nitrogen a year. Minor pruning is needed, but necessary to decrease disease and increase fruit size. You must also remember to remove the suckers from the base of the plant.
The fruit takes five to seven months to mature after it blossoms. The fruits are usually harvested September to December. Almost all harvesting is done by hand. After being picked they should be kept at optimal conditions of 32 to 41 degrees Fahrenheit and 80 to 85% relative humidity. Pomegranates can be kept that long for up to seven months. The long storage improves the flavor of the fruit.
An easy method of propagation is to do it by seed. The seeds of the pomegranate germinate very quickly, even if sprinkled on the top of the soil. They usually have little problem with dormancy since the tree is native to warm climates. Seeds are also more economical than other methods of propagation. The biggest problem with seed propagation is that they are not true to type, and can loose some of the good qualities of the established cultivars. That is why the seed propagation is not used in large-scale production. It also takes longer for a fruit producing plant to grow from seed than other methods.
Hardwood cuttings are the most widely used method. You should take the cuttings November through January off of one-year-old wood. One source said the cuttings should be six to ten inches long while another source suggested cuttings of twelve to twenty inches in length. Treat the cuttings with a growth regulator and let them develop some roots in a greenhouse before planting in the spring. The cuttings are the best way to keep the properties of the original cultivars.
Grafting of pomegranate trees is rarely done in the United States. It is sparsely used in other parts of the world. Many different types of grafts have not been successful enough for use in commercial production. I have not found much information explaining why there is such difficulty getting successful grafts.
Tissue culture is another method of production that calls for the growth of the plant in a sterile environment using the tissue, seed, or cuttings. There is little, if almost no tissue culture of pomegranates. The United States has such a small pomegranate market that very little money is put into its research and the expense of tissue culture. Many of the countries that have large pomegranate production have poor economical status and cannot provide much money to its research.
I would have liked to find more specific information on the propagation of pomegranates. Since the fruit has been grown for hundreds of years with reliable results there is not much want for growers to explore other options. The minimal U.S. production posed a problem in finding information also. It was very easy to find general production knowledge and facts, but in depth statistical information is very hard to come by. The propagation of pomegranates has been done for many years and the plant has endured.
California Rare Fruit Growers. “Pomegranates.” June 4, 1997.
Corbis Photo Search. “Pomegranate.” April 26, 2003. <http://www.corbis.com>.
Gernot Katzer’s Spice Dictionary. “Pomegranates.” February 27, 2000.
POM Wonderful. July 14, 2001. <http://www.pomwonderful.com/home.asp>.
Pomegranate. March 24, 1999. <http://www.hort.purdue.edu/newcrop/morton /pomegranate.html>.
Virginia Cooperative Extension. “Pomegranates.” November 1, 1997.